Are you adding weight to the back of your truck for driving in mud and snow? if not that could be a big part of your problem. I have Michelin LTX/MS2s on my truck and they are amazing in snow, slush and rain. I would not say they are excellent in the mud, but I have never been stuck with them in either. I use 5 sand bags in the winter and when hunting I usually carry all of the gear, which is at least 300 pounds. I rarely have to put my truck in 4 wheel in the winter, but I always put it in 4 wheel before going off road.
I had Cooper Discoverer ATRs (discontinued now)on it before the Michelins. They were slightly better off road with their aggressive tread blocks, but were not as good in the slush and rain. I replaced them early because at a little over half worn, wet traction really suffered and they had to go. My truck sees about 90% highway use and if I am deep off road I am not alone, so I went with a highway tire this time. I have been happy with my choice.
My truck at work is a 2wd 1 ton Econoline cube van. It has Goodyear Wrangler HTs on it. We have a dirt field that has a few spots that turn to mud every time it rains. Unloaded it slips a bit but usually makes it through. Loaded it has no trouble at all. In the snow it really does well and they never plow the lot for us at night. Again weight helps a lot. It usually has between 500 and 2500 pounds in it, and it never sees pavement and never leaves the lot.
My friend has BFG All-Terrain T/A KOs on his Tacoma. They are great in the mud. I am usually behind him in the mud hunting, his truck is unloaded but also has a locker. They are good in deep snow but only fair in slush and heavy rain. He does not add weight for winter but does use 4 wheel when it snows or is slushy. I think his truck would do much better with a couple sand bags. He has 40k miles on them and they still look good.